Assessing and predicting the impacts of ozone (O3) concentration on crop production have been drawing great attention in the scientific community. The ambient O3 concentration above the winter wheat field was observed with ML9810B O3 Analyzer in Jiaxing, Zhejiang Province. The impact of O3 on the wheat leaf photosynthesis was measured in open-top chamber. Based on the observed parameters, a numerical model for simulating the impact of O3 on the winter wheat development and yield was established, by added the effects of O3 on ear photosynthesis and leaf area. The results showed that the model properly simulated the impacts of O3 on wheat growth in field. The relative error of predicted biomass was 10.3%. The accumulated loss of photosynthate was 11.4% and yield loss was 17.8% at ambient O3 concentration in the wheat growth period under sufficient moisture and fertilizer supplies.